A buck converter, also called buck regulator or DC-DC step-down switching regulator, is a type of DC-DC converter that provides an output regulated voltage that is lower than its input voltage.
ST's monolithic step-down (buck) converter ICs offer input-voltage capability up to 61 V and deliver output currents up to 4 A with high switching frequency.
These buck regulators embed a full set of protection functions (overcurrent, overvoltage, and over-temperature) to increase the mean time between failures (MTBF) and reduce the number of external components required, thus lowering BOM costs.
Monolithic buck converter ICs (buck regulator) for any application requirement
Applications
Buck converters can be used for a large number of applications.
- ST offers high performance and high flexibility AEC-Q100 compliant buck converters for automotive applications.
- See all Automotive buck converters
- High reliability and excellent robustness buck converters, for industrial and any application requiring a wide range of input output voltages.
- See all Industrial buck converters
Product types: how to choose the right buck converter
Learn about ST broad selection of buck converters, designed to meet a wide range of requirements.
When a well-regulated rail is needed with minimum design effort, ST’s DC-DC portfolio jhas the right solution. Moreover, the need for only a few external components, internal compensation and synchronous rectification do not compromise performance and features.
Adjustable loop bandwidth, external clock synchronization, and adjustable soft start are some of the key features which allow designing a tailored solution for the final application.
In systems where low power consumption is a must, like battery- or bus-powered applications, the buck converter needs to be very efficient in the conditions where the system is in idle state for most of the time.
Low-consumption buck converters feature ultra-low quiescent current and high efficiency at light load to meet these application requirements.
Low-consumption buck converters feature ultra-low quiescent current and high efficiency at light load to meet these application requirements.
Buck converters offer a significant advantage in terms of efficiency compared to linear regulators.
However, they also introduce switching noise that could represent a big obstacle to comply with EMI standards and disturb noise-sensitive applications.
Low-noise buck converters help designers meet these challenges.
However, they also introduce switching noise that could represent a big obstacle to comply with EMI standards and disturb noise-sensitive applications.
Low-noise buck converters help designers meet these challenges.
The main target application of the isolated buck topology is to get a floating-voltage source. This is commonly required to provide supply to high-side gate drivers in high-power DC-DC converters, inverters, motor drivers, and other industrial applications.
Wide input voltage (VIN) buck converters comply with unregulated input voltages or with bus voltages subjected to strong line transients typically occurring in industrial and telecom systems.
A short on-time ensures a large input-to-output conversion ratio while maintaining a high switching frequency.
A short on-time ensures a large input-to-output conversion ratio while maintaining a high switching frequency.
Benefits
- High-voltage technology together with high reliability, robustness, and compactness
- High efficiency at any load and a high level of performance for consumer and computer products
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About buck converters
How does a buck converter work?
A buck converter usually uses two switches and an inductor to make a voltage controlled current source that interacts with the parallel combination of output capacitor and load, to generate the desired output voltage (VOUT < VIN).
Where and why is a buck converter used?
A buck converter is used to step down the voltage of a given input to achieve the required output voltage. Buck converters can be used in many applications, including smartphones, tablets, battery-powered equipment, industrial power systems and point-of-load supplies.
What are the advantages of a buck converter?
Buck converters offer a more efficient solution with fewer, smaller external components. They can step-down voltages using a minimal number of components. In the same time, they offer a lower operating duty cycle and higher efficiency across a wide range of input and output voltages.
- L5983 1.5 A step-down switching regulator
- L5985 2 A step-down switching regulator
- A7987 61 V 3A asynchronous step-down switching regulator with adjustable current limitation for automotive
- ST1PS03 400 mA nano-quiescent synchronous step-down converter with digital voltage selection, Power Good and independent Load Switch
- ST1PS01 400 mA nano-quiescent synchronous step-down converter with digital voltage selection and Power Good
- L5980 0.7 A step-down switching regulator
- ST1S09 2 A, 1.5 MHz PWM step-down switching regulator with synchronous rectification
- L5981 1 A step-down switching regulator
- A5972D Up to 1.5 A step-down switching regulator for automotive applications
- A5973AD Up to 1.5 A step-down switching regulator for automotive applications
- L7983 60 V 300 mA synchronous step-down switching regulator with 10 µA quiescent current
- A5970AD Up to 1 A step down switching regulator for automotive applications
- A5970D Up to 1 A step-down switching regulator for automotive applications
- L6983 38 V, 3 A synchronous step-down converter with 17 µA quiescent current
- A5973D Up to 2 A step down switching regulator for automotive applications
- A6902D Up to 1 A step down switching regulator with adjustable current limit for automotive applications
- L5973D Up to 2 A step down switching regulator
- AST1S31HF Up to 4 V, 3 A step-down 2.3 MHz switching regulator for automotive applications
- ST1S14 Up to 3 A step-down switching regulator
- L5972D 2A switch step down switching regulator
- L7981 3 A step-down switching regulator
- ST1S30 3 A, 1.5 MHz PWM step-down switching regulator with synchronous rectification
- L7980 2 A step-down switching regulator
- ST1S31 3 A DC step-down switching regulator
- L6984 36 V, 400 mA synchronous step-down switching regulator
- L6986 38 V, 2 A synchronous step-down switching regulator with 30 µA quiescent current
- PM8903A 3 A step-down monolithic switching regulator
- L4964 High current switching regulator
- L6986I 38 V, 5W synchronous iso-buck converter
- A6986I Automotive 38 V, 5W synchronous iso-buck converter
- L5988D 4 A continuous (more than 5 A pulsed) step-down switching regulator with synchronous rectification
- A5974D Up to 2.5 A step down switching regulator for automotive applications
- L6986H 38 V, 2 A synchronous step-down switching regulator with 30 µA quiescent current
- L296 HIGH CURRENT SWITCHING REGULATORS
- L5970D Up to 1 A step down switching regulator
- AST1S31 Up to 4 V, 3 A step-down 1.5 MHz switching regulator for automotive applications
- L4978 2A Step down switching regulator
- L7987 61 V 3 A asynchronous step-down switching regulator with adjustable current limitation
- ST1S50 4 A Monolithic synchronous step-down converter with high efficiency at light load
- STPD01 Programmable Buck Converter for USB Power Delivery
- L5973AD 2 A switch step down switching regulator
- A6986F Automotive 38 V, 1.5 A synchronous step-down switching regulator with 30 µA quiescent current
- L6986F 38 V, 1.5 A synchronous step-down switching regulator with 30 µA quiescent current
- ST1S15 500 mA, 6 MHz synchronous step-down converter
- ST1PS02 400 mA nano-quiescent synchronous step-down converter with digital voltage selection, Power Good and AUX switch
- L4976 1 A step down switching regulator
- A5975D Up to 3 A step down switching regulator for automotive applications
- A6984 36 V 400 mA synchronous step-down switching regulator
- A5975AD Up to 2.5 A step down switching regulator for automotive applications
- ST1S03 1.5 A, 1.5 MHz adjustable, step-down switching regulator
- L4973 3.5 A step down switching regulator
- ST1S10 3 A, 900 kHz, monolithic synchronous step-down regulator IC
- L4971 1.5A Switching Regulator
- ST1S06 Synchronous rectification with inhibit, 1.5 A, 1.5 MHz fixed or adjustable, step-down switching regulator
- L4970A 10 A switching regulator
- L4963 1.5 A SWITCHING REGULATOR
- ST1S12XX Synchronous rectification with enable, 0.7 A, 1.7 MHz fixed or adjustable step-down switching regulator in TSOT23-5L
- A7986A 3 A step-down switching regulator for automotive applications
- A7985A 2 A step-down switching regulator for automotive applications
- L4972 2 A SWITCHING REGULATOR
- ST1S40 3 A DC step-down switching regulator
- L6926 High efficiency monolithic synchronous step-down regulator
- ST2S08B Dual synchronous rectification, 1.5 A, 1.5 MHz adjustable step-down switching regulator
- L4975A 5 A switching regulator
- L6981 38 V, 1.5 A synchronous step-down converter with low quiescent current
- L6983I 38 V 10W synchronous iso-buck converter for isolated applications
- L5986 2.5 A step-down switching regulator
- L5987 3 A step-down switching regulator
- L5970AD Up to 1 A step down switching regulator
- A6986 38 V, 2 A synchronous step-down switching regulator with 30 µA quiescent current
- A6985F Automotive 38 V, 500 mA synchronous step-down switching regulator with 30 µA quiescent current
- L6985F 38 V, 500 mA synchronous step-down switching regulator with 30 µA quiescent current
- L7987L 61 V 2 A asynchronous step-down switching regulator with adjustable current limitation
- PM8908 Monolithic buck converter for DDR memory termination
- ST1S32 4 A DC step-down switching regulator
- L6902 Up to 1 A switching regulator with adjustable current limit
- ST1S41 4 A step-down switching regulator
- ST2S06 Dual synchronous rectification with reset or inhibit, 0.5 A, 1.5 MHz adjustable step-down switching regulator
- L7985 2 A step-down switching regulator
- L7986TA 3 A step-down switching regulator
- L6982 38 V, 2 A synchronous step-down converter with low quiescent current
- L3751 Wide 6 V to 75 V input voltage synchronous buck controller
- L7986 3 A step-down switching regulator
- L6928 High efficiency monolithic synchronous step-down regulator
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